Araucaria moist forests

This ecoregion spans the mountainous areas of southern Atlantic Brazil and extends into northeastern Argentina. These forests are a relict of a once widespread ecosystem of mixed coniferous and broad-leafed trees, spread out across a mountainous landscape. Forests spread from middle-level plateaus of around 500m to the high slopes of the Serra da Mantiqueira, which rise to 1600m above sea-level. The climate is subtropical with frequent frosts and without a dry season. Annual precipitation is high, and ranges from 1300-3000mm. These mixed forests are convergent with savanna regions to the south, cerrado scrub to the north, and moist forests to the east and west. Less than one percent of the ecoregion is covered by protected areas (Silva & Dinnouti 1999). More reserves are needed to save these biologically rich forest from illegal logging and urban expansion.

Scientific Code

(NT0101)

Ecoregion Category

Neotropical

Size

83,400 square miles

Status

Critical/Endangered

Habitats

Description Location and General DescriptionBrazilian Araucaria moist forests are bordered on the north and west by Paraná-Paranaíba forests, on the south by the Pampas, and on the east by Serra do Mar moist forests. Most of this ecoregion is on sedimentary rocks of the Paraná Plateaus. The climate is subtropical with frequent frosts and with no dry season. Annual precipitation shows a significant variation between 1,300 mm and 3,000 mm (Hueck 1972). Soils throughout the ecoregion range from fertile latosols to impoverished lithosols. Forests are spread from middle-level plateaus, 500 m elevation, to the high slopes of Serra da Mantiqueira, 1,600 m elevation (Klein 1960, Hueck 1972). The main vegetation is Atlantic moist forest, with a particular 45 m tall emergent strata of the Brazilian Araucaria (Araucaria angustifolia) (Veloso et al. 1991). Canopy layers are rich in species of Lauraceae (Ocotea pretiosa, O. catharinense), Myrtaceae (Campomanesia xanthocarpa), and Leguminosae (Parapiptadenia rigida) (Klein 1960). Although apparently homogeneous, Brazilian Araucaria moist forests vary a lot in both composition and structure. These forests form complex mosaics of plant associations among the pioneer Brazilian Araucaria and tree species from different types of Atlantic forest (Leite & Klein 1990). This ecoregion also includes an interesting association of Brazilian Araucaria with grasslands (Klein 1960, Hueck 1972). Because of its unique features of climate, geomorphology and floristic composition, Brazilian Araucaria moist forests are easily set apart from other portions of the Brazilian Atlantic forest.

Biodiversity FeaturesBrazilian Araucaria moist forests represent a extraordinary mosaic combining species from a relict coniferous forest (including several Andean genera) with Atlantic forest species. In this mosaic, several endemic species are found. Among 352 plant species recorded in this region, 47 (13.3 percent) are endemics (Leite & Klein 1990). This moist forest ecoregion is recognized as an important Endemic Bird Area (Wege & Long 1995). It is also home for Atlantic endemic and threatened vertebrates such as the brown howler monkey (Alouatta fusca) and the red spectacled Amazon (Amazona petrei) (Mendes 1990, Wege & Long 1995), which have few populations scattered in remnants of these forests. Other rare mammal include the Guianan squirrel (Sciurus aestuans), and Paca (Agouti paca). Threatened vascular plant species also survive here, including the Brazilian Araucaria (Klein 1990, São Paulo 1998). From a evolutionary perspective, Brazilian Araucaria moist forests represent more widespread South America coniferous forests of the past (Rambo 1951, Klein 1960, Veloso et al. 1991) and, therefore, have great importance for conservation.

Current StatusThese moist forests have been reduced in area by 87 percent (SOS MATA ATLÂNTICA 1998). Remaining vegetation is represented by 35,045.67 km2 of mixed forests. Few large blocks of habitat are preserved by official protection. In addition, thousands of private 1 to 100 ha remnants surrounded by pastures and agriculture represent a significant part of remaining vegetation. Protected areas cover only 0.62 percent of the ecoregion (Silva & Dinnouti 1999).

Types and Severity of ThreatsIllegal timber extraction and forest conversion into agricultural lands represent a large threat to the future of these forests because they possess fertile soils that are attractive to agricultural interests.

Justification of Ecoregion DelineationBrazilian Araucaria moist forests comprise a well delimited patch of Atlantic forest associated with coniferous species- a mixed forest. All botanical classifications rank such forests as a type of the Atlantic forest complex (e.g., Hueck 1972, Veloso et al. 1991, Rizzini 1997). The delineation’s for the Araucaria Moist Forests were derived by lumping vegetative coverage units of the IBGE map (1993) to trace the historic distribution of Brazilian Araucaria (Araucaria angustifolia) forests (Mata de Pinheiros). The following coverages were lumped: all Mata de Pinheiros classifications (montane ombrophilous mist forest, upper montane ombrophilous mist forest, and secondary vegetation), and within the broader perimeters of these forest types, all agricultural activities and savanna vegetation were lumped. Linework was then reviewed and modified by N. Vlarty (pers. comm.) and during a priority setting workshop(10-14 August, 1999, Atibaia, Sao Paulo, Brazil and WWF in prep.). Linework extensions for limits of this ecoregion into Argentina were done by expert opinion from this workshop.